Controlling device for turbines.



S. W. RUSHMORE.

CONTROLLING DEVICE FOR TURBINES.

APPLICATION FILED sEPT.28. 1911.

1 ,2l 2,81 Pafeen-ted Jan. 16, 1917. RI l Cc) O N QQ O JP I l I l w I l l l l l o I I. i |I 'l ll /l l D I 1,//l//l ab NVENTOI? 1 ED-rsfrATEs lPATENT onFicEg.

SAMUEL w. mIsHMonE, orPLAINFIELD, NEW JERSEY.

coN'rnoLLiNG DEVICE ron Tunimns.

, Patented Jan. 16, 1917.

Application led September 28, 1911. Serial No. 651,819.

'been used to some extent, but their applica-` tion has been greatly-restricted by reason of the large first cost and excessive cost of operation and repair, while on most raiL ways the electric arc light has been found too blinding, for instance to signal-men and engineers on trains coming from the opposite direction.

Attempts have been made to employ headlights fitted with the modern, high power,

metal filament, incandescent lamps, but it has been found difficult properly to control .y thespeed of the turbines suitable for the extremely small amount of energy demanded by such lamps, particularly asy such lamps require extremely close voltage regulation. It has been found to be impracticable to A control the speed of the very small turbinesoperating on very high steam pressure by means of the usual centrifugal governors loperating a throttle valve, as such governors require closer attention than can be given upon a locomotive, and the high pressure steam soon Wears away the valve seats,

thus permitting the speed to become excessiv'e. Furthermore such governors are costly and require a large amount of space in relation to the size of the turbine.

` In my turbine I employ'av centrifugal govi ernor device which does not control the steam supply, but acts .asa brake to apply a load when the speed tends to become excessive. I place the rubbing parts of the brake device within the turbine casing Where the exhaust steam acts as a lubricant to prevent delivered by the dynamo, the waste is neg-- ligible, as'the turbine will be operated only when the headlight ,is to be li hted, and the size of the s /am nozzle will e adjusted to pass only about the'quantity of steam required to do the work.

A single stage turbine directed to a simple and compact embodiment of myinvention is shown in the accompanying drawing in which the reference numerals of this description are applied to the corresponding parts in both of the figures of which- Figure 1 is a longitudinal, vertical, sectional view and Fig. 2 a cross sectional View taken on line 22 of Fig. A1. V

In the drawing the usual casing C is composed of the right and left castings 1 and 2, flanged at 3 for the securing bolts 4 and having formed integral therewith the pedestal 6, resting on a suitable base 7. Said casing is formed with the bearing flanges 9-9, tted with bushings 10-10 for the shaft S journaled therein. Keyed on said shaft within the casing is the usual rotor, or bucket-wheel, R, to which power is communicated through the action of steam, from the usual nozzles, N, acting on the vanes, or buckets, 12 arranged on the periphery of the rotor R. M indicates the generator mounted on and driven by the shaft S.

Preferably/within that part of the casing which forms the exhaust chamber indicated at 15, I provide an annularbraking flange 16 having an inner, peripheral, braking surface to be engaged by centrifugal brake shoes 18. By thus arranging the brake within the casing, the parts are subjected to the action of the steam in its passage to the exhaust ports 19, whereby a constant lubri--` cation of the friction surfaces and absorption by the steam ofthe heat generated by friction will follow.

As hereshown the brake shoes 18 of my invention desirably may be pivoted at 20 on the/rotor, R, to be forced directly byV centrifug/al action into lbraking contact with the fiange 16, thus controlling the speed. The forming of the brake-shoes with counterbalance weights 22 as shown permits the brake-shoes to be of\substantial proportions to employ the maximum braking area while confining the centrifugall action within the proper limits to `accord therewith. Supported in lugs 24 von the rotor are the shoeretracting springs 25 in engagement with notches 26 in the shoes normally to hold said shoes in retracted position and to insure disengagement at low speeds'. This retraction is limited by stop-lugs 28 onwthe rotor. j

The structure and arrangement here described is strong, simple and durable, and of great value in making possible the use of incandescent lamps on locomotives.

Having described my invention, I claim:

1. In combination,` a stationary member having ,a braking surface, a rotary member, a braking element pivotally connected to the rotary member and having a brake shoe 1n juxtaposition to said braking surface, whereby the centrifugal force of the rotary member will apply the brake shoe to said braking 1 surface with more or less pressure depending upon the speed of rotation of the rotary member, and a counterweight arranged to partly offset the centrifugal eHect of said brake shoe.

2. A turbine including a stationary member having a braking surface, a rotary blade carrying member, and a braking element pivotallyconnected to the rotary member and having a said braking surface, whereby the centrifugal force of the rotary member will apply the brake shoe to said braking surface with more or less pressure dependingupon the speed of rotation of the rotary member,'and a weight carried by said braking element to limit itsbraking action.

3. In a turbine, a stationarycasing having a braking surface, and a steam inlet and a steam outlet, a rotary blade carrying member within said casing, and a braking elej vment pivotally connected to the rotary member in the path of the steam and having a A brake shoe in juxtaposition-to said braking surfaces whereby the centrifugal force of the rotary member will apply the brake shoe to said braking surface and whereby the steam passing to the outlet will lubricate the braking surfaces. o l

' 4. In a controlling device for turbines, a casing inclosing a steam chamber, a rotary member arranged in said chamber, an annular braking flange within `the chamber, centrifugally acting brake-shoes pivotally carried on the r'otary member to engage said ange when the speed becomes excessive, said brake-shoes having an enlarged braking area, counter-balance weights carried by the shoes to limit their centrifugal action, stoplugs on the rotor and retractile springs-norto hold the shoes in retracted position mally said parts bein engagement with the lugs,

brake shoe in juxtaposition to -to engage said stationary member, said brake-shoes having an enlarged braking area, counter-weights to oppose the centrifugal action of said shoes in order to limit the braking and retractile springs normally to hold the shoes in retractedposition.

,l 6. In combination a casing having a fluid inlet and 'a fluid outlet, a rotary member within said casing, a stationary member within said casing, and centrifugally acting brake shoes carried by'said rotary member for` frictionally engaging 4said stationary member when the speed of said rotary member exceeds a pretermined limit, the passage of fluid through said casing serving to dissipate the heat generated by the friction and to lubricate the friction surfaces.

7. A controlling device for turbines and the like, including a casing having a steam chamber, a rotary member withinsaid chamber and carryiilng a plurality of centrifugally actuated bra 'ng parts and said casing carrying a xed surface with which' said parts may engage' as the speed of said rotary member exceeds a predetermined limit, and said casing having, a steaminlet and a steam outlet whereby the assage of steam through said casing may iss'ipate the heat generated by the friction of said parts on said surface. 8. A power absorbing braking governor including a stationary member presenting a braking surface, a rotary member and a braking element carried by said rotary meniber and having a brake Shoe juxtaposed to said braking surface whereby the centrifugal force of the rotary member will apply the brake shoe to said braking surface` with more or less pressure, depending upon the speed of rotation .of the rotary member, and a counterweight connected to said brake shoe and subjected to the action of centrifugal force to partlyk counteract the effect of centrifugal force on said brake shoe.

In testimony whereof I have signed my name to this specification in the presence of ltwo subscribing witnesses.

SAMUEL W. RUSI-IMORE.

Witnesses:

V. N. Dn LAM/ATER, E. W. IoiNrER. 

